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81.
Minoru Umezu 《Astrophysics and Space Science》1998,259(4):343-354
We find that the hydrogen flux near the boundary of the semiconvection zone with Ledoux's neutral condition is unreasonably
positive while it is reasonably negative throughout the semiconvection zone with Schwarzschild's neutral condition.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
82.
Minoru Umezu 《Monthly notices of the Royal Astronomical Society》1998,298(1):193-206
The treatment of the overstable zone by Langer, Sugimoto &38; Fricke is extended so that the effects of radiative heat loss from convective elements and of the mixing length are included. As the overstability investigated by Kato arises because of the radiative heat loss from the convective element, this loss may play a role in the heat flux. In the formulation presented in this work, the diffusion coefficient depends on the mixing length when the mixing length is very small. In calculations with the method of Langer et al., the efficiency factor of the diffusion coefficient of chemical species is sometimes much smaller than 1. This exceedingly small efficiency factor may be explained by the dependence of the diffusion coefficient on the mixing length. We find that the neutral condition of Kato's overstable zone is ∇ rad = ∇ ad . 相似文献
83.
Edward D. Goldberg Minoru Koide Kathe Bertine Vern Hodge Martha Stallard Darko Martincic Nevenka Mikac Marco Branica Jamal K. Abaychi 《Applied Geochemistry》1988,3(6)
Inorganic surfaces sorb dissolved and particulate phases from seawater onto organic films from a variety of sources. Heavy metals such as Au, Pt, Mn and Cd come to the coatings primarily from particulate phases. This observation confirms a previous finding of this laboratory for the uptake of U, Pu and Po. With depth in the open ocean there are greater contributions from the dissolved phases. Microbial and photochemical processes can enrich surfaces in some metals through reduction reactions. Copper and Mn enrichments in the films are attributed to the photo-reductions of Cu(II) to Cu(I) and manganese oxides to Mn(II), respectively, while the uptake of Mo is a consequence of the reduction, mediated by organisms, of molybdate to Mo(V) or Mo(IV). Cadmium, on the other hand, appears to be bioaccumulated in the films. 相似文献
84.
Geostructural setting, as well as mineral and isotopic compositions, of separate apatite deposits and occurrences in the Aldan Shield composed of Precambrian metasedimentary apatite–carbonate rocks are considered. In terms of carbon and oxygen isotopic compositions, they differ from other carbonate rocks of the Aldan Shield, including carbonatites and Ca–Mg metasomatites, and resemble Phanerozoic and Precambrian metasedimentary carbonates. They formed in oxidizing conditions. The contribution of evaporite processes at different stages of their formation is supported by the carbonate enrichment in 13C and the presence of sulfates. It was established that apatite–carbonate rocks represent the product of complex alternation of sedimentary processes at different values of salinity in the basins occasionally characterized by the decomposition of older sediments under subaerial conditions. 相似文献
85.
Journal of Oceanology and Limnology - 相似文献
86.
Takeshi Naganuma C. Julius Meisel Hideki Wada Yukihiro Kato Akira Takeuchi Katsunori Fujikura Jiro Naka & Kantaro Fujioka 《Island Arc》1999,8(2):232-244
A biological community was discovered in the Northern Okushiri Ridge, northeastern Japan Sea. The community was closely associated with sea-floor fissures, and presumed to be supported by methanotrophic and/or thiotrophic bacterial production. Sediments inside of and in the vicinity of the fissures were collected, and the short-chain (C9–20 ) sediment fatty acids were analyzed for amounts and compositions. The fatty acid compositions were compared with those from a known methane seep and a submarine volcano in the Sagami Bay, central Japan, and from a whale skeleton at the Torishima Seamount, northwestern Pacific Ocean. As a result, a close relationship between the sediments from the Northern Okushiri Ridge, the known methane-seep, and the whale skeleton was found. This finding represents the first discovery of methane seepage and associated biological communities in the Japan Sea. This also supports the hypothesis that the eastern margin of the northern Japan Sea is at the early stage of new subduction. 相似文献
87.
Sato Minoru Oba Takashi Hosokawa Takao Yamaguchi Toshiyasu Nakano Toshiki Saito Tadao Muramoto Koji Kahara T akashi Funayama Katsura Kobayashi Akio Nakano Takahisa 《中国海洋大学学报(英文版)》2005,4(3):209-213
Brown alga ( Undaria pinnatifida) was treated with alginate lyase and hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for the angiotensin-I-converting enzyme (ACE) was measured. Four hydrolysates with potent ACE-inhibitory activity were administered singly and orally to spontaneously hypertensive rats (SHRs). The systolic blood pressure of SHRs decreases significantly after single oral administration of the brown alga hydrolysates by pro- tease S ' Amano' (from Bacillus stearothermophilus) at the concentration of 10 (mg protein) (kg body weight)^ - 1. In the 17 weeks of feeding experiment, 7-week-old SHRs were fed standard diet supplemented with the brown alga hydrolysates for 10 weeks. In SHRs fed 1.0 and 0.1% brown alga hydrolysates, elevating of systolic bloodpressure was significantly suppressed for 7 weeks. To elucidate the active components, the brown alga hydrolysates were fractionated by 1-butanol extraction and HPLC on a reverse-phase column. Seven kinds of ACE-inhibitory peptides were isolated and identified by amino acid composition analysis, sequence analysis, and LC-MS with the results Val-Tyr, Ile-Tyr, Ala-Trp, Phe-Tyr, Val-Trp, Ile-Trp, and Leu-Trp. Each peptide was determined to have an antihypertensive effect after a single oral administration in SHRs. The brown alga hydrolysates were also confirmed to decrease the blood pressure in humans. 相似文献
88.
Minoru Oda 《Astrophysics and Space Science》1989,160(1-2):19-25
On the basis of my experience in the X-ray astronomy, and on some typical highlights of multi-wavelength observations, I emphasize the importance of collaboration between space astronomy and ground-based astronomy.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 2, 1988. 相似文献
89.
90.